1. Field of the Invention
The present invention relates to a data structure, an image processing apparatus, an image processing method, and a program, and more particularly, to a data structure, an image processing apparatus, an image processing method, and a program for allowing a user to watch a 3D content without feeling uncomfortable no matter whether the user watches the 3D content as a 3D image or a 2D image.
2. Description of the Related Art
2D images are mainly used as video contents. Recently, however, 3D images attract attention. For example, as shown in Japanese Patent Application Laid-Open Nos. 10-327430 and 2008-182669, various techniques have been suggested for 3D image display apparatuses and 3D image encoding and decoding methods.
A 3D image is constituted by a left eye image seen with a left eye and a right eye image seen with a right eye. Each of the left eye image and the right eye image has predetermined parallax, so that a user can recognize the images as a stereoscopic image.
Recent 3D movies employ a technique for inserting a black border to a periphery of an image frame in order to allow a user to easily see an image in the periphery of the image frame (exterior edge portion of the image). The size of the black border is dynamically changed according to the amount of parallax (parallax amount) in a scene. Accordingly, the black border is also referred to as a floating window.
FIGS. 1A to 1C are figures illustrating an example of insertion of a black border.
FIG. 1A is an example of a 3D image with the amount of protrusion being zero. In each of a left eye image and a right eye image, the display position of an apple is the same. Accordingly, the amount of protrusion is zero.
FIG. 1B is an example of a 3D image in which an apple appears to be protruding. When the 3D image of FIG. 1B are compared with the 3D image of FIG. 1A, it is understood that the apple in the left eye image in the 3D image of FIG. 1B is shifted to the right side (inner side of the image) by X. In other words, there is parallax between the apple in the left eye image and the apple in the right eye image, and the parallax amount is X. Accordingly, the apple appears to be protruding. However, no black border is inserted into the 3D image of FIG. 1B. The absence of black border makes a protrusion at the image frame. Accordingly, a user would have difficulty in seeing the 3D image (feel uncomfortable).
FIG. 1C is an example where a black border is inserted into the 3D image of FIG. 1B. The black border having the same width as the parallax amount X is inserted into the left eye image of FIG. 1C. As a result, the image is easy for the user to see.